A plethora of patented swimming pool covers have been available for safety purposes and/or preserving the cleanliness of the water in swimming pools during cold seasons when the pool is not in service. The covers, of course, prevent contaminants, such as dirt, leaves, branches, etc., and other foreign matter from entering the water. The prior art covers typically require substantial manufacturing efforts and concomitant high costs occasioned by providing such covers with grommets, straps, ballasting means, mechanical locking devices, thickened borders, draw ropes, and like structure for use in anchoring the cover to the pool or otherwise securing it about the pool periphery.
Typical of such prior art covers are those shown in U.S. Pat. Nos. 3,354,472; 3,355,745; 3,427,663; 3,523,308; 3,593,757; and 3,667,070. All of the prior art covers require substantial manufacturing effort, must be cut to precise sizes, and are difficult to install about and/or anchor to pool structures. Therefore, they are very expensive to manufacture and are costly to the consumer.
In accordance with the present invention, a new and improved drumhead type swimming pool cover may be manufactured simply by cutting any known swimming pool cover material to rough sizes and rough shapes greater than those of the pool to be covered and sufficient for the cover to drape over the edges of the pool in drumhead fashion. The new cover may be fastened to most existing above-ground pools and, indeed, may be fastened to all pools constructed, in accordance with the principles of the present invention, with a coping member provided with a male locking lip of predetermined configuration to be described hereinafter. Typically, the locking lip is in the nature of a curled rail or the like, which extends from a vertical outer wall of the coping and which has a free edge which projects upwardly and outwardly with respect to the pool being covered.
The sheet material comprises the drumhead cover which is clamped securely in place, in accordance with the invention, by an elongated, extruded plastic, snap-on channel member which engages the locking lip around the peripheral portions of the pool and clamps the cover sheet securely therebetween. The internal cross-sectional configuration of the locking channel is substantially congruent with the cross section of the locking lip. In accordance with a more specific principle of the invention, the cooperating configurations of the locking lip and the locking channel are such that the loading of the pool cover after its installation, such as by fallen leaves, the formation of a pool of rain water or melted snow thereupon, will cause the clamping and locking action to be enhanced, with a resultant tightening of the gripping of the cover member to the pool coping.
As a most important advantage of the practice of the present invention, the main component of swimming pool cover assemblies, i.e., the cover sheet, may be manufactured simply and expenditiously by unskilled labor merely by cutting sheet material to size. No labor whatever is required for the installation of grommets, locks, or other anchoring hardware to the cover, nor is any labor or material required to specially shape the cover or its edge portions. Indeed, by the provision of standard, universal, or modular locking channels, which are configured to effectively mate with a wide variety of locking lip configurations, the manufacturing costs of complete swimming pool cover assemblies will be further reduced to a bare minimum.
For a more complete understanding of the present invention and a better appreciation of its attendant advantages, reference may be made to the following detailed description taken in conjunction with the accompanying drawings.